1. Field of the Invention
The present invention relates to an image processing apparatus which forms modified images from original images.
2. Brief Description of the Related Art
An image processing apparatus which performs magnification (enlargement or reduction), rotation, affine conversion or slantwise mapping of an original image is well known. For example, affine conversion is to perform, simulataneously, magnification, rotation, and shifting of the original image. Slantwise mapping is to convert a rectangular original image into an image having the shape of a non-rectangular parallelogram.
In such a modification or conversion, calculations of addresses are necessary. These calculations are very complicated and involve multiplications and divisions, so that it takes a relatively long time to obtain the necessary addresses.
Further, it takes several times, or even dozens of times, as long for the micro processor to perform a multiplying process as to perform an adding or reducing process. Namely, the more the multiplying processes, the longer the operation time.
In the conventional method, operations for calculating original addresses and destination addresses have some multiplying processes so that it takes much time to form the modified images, e.g., a rotated image.